Strings
A JavaScript string stores a series of letters, numbers, and punctuation characters. For example, a string could contain the word "Ollie". To define a string's value, wrap the desired characters in double or single quotes. The quotes are not part of the stored value. String indices are zero-based: The first character is position 0, the second is 1, etc.
var robot = 'Ollie';
var report = "Wow! Ollie just did a 720 in mid-air!";
String Properties
constructor returns the string's constructor function
length returns the length of a string
prototype allows you to add properties and methods to an object
String Methods
charAt() returns the character at the specified index (position)
charCodeAt() returns the Unicode of the character at the specified index
concat() joins two or more strings, and returns a new joined strings. You can also use the + operator to do this.
Example: combine strings before speaking:
async function startProgram() {
var start = "This is a ";
var end = "complete sentence.";
speak(start + end);
await delay(2.0);
}
endsWith() checks whether a string ends with specified string/characters
fromCharCode() converts Unicode values to characters
includes() checks whether a string contains the specified string/characters
indexOf() returns the position of the first found occurrence of a specified value in a string
lastIndexOf() returns the position of the last found occurrence of a specified value in a string
localeCompare() compares two strings in the current locale
match() searches a string for a match against a regular expression, and returns the matches
repeat() returns a new string with a specified number of copies of an existing string
replace() searches a string for a specified value, or a regular expression, and returns a new string where the specified values are replaced
search() searches a string for a specified value, or regular expression, and returns the position of the match
slice() extracts a part of a string and returns a new string
split() splits a string into an array of substrings
startsWith() checks whether a string begins with specified characters
substr() extracts the characters from a string, beginning at a specified start position, and through the specified number of characters
substring() extracts the characters from a string, between two specified indices
toLocaleLowerCase() converts a string to lowercase letters, according to the host's locale
toLocaleUpperCase() converts a string to uppercase letters, according to the host's locale
toLowerCase() converts a string to lowercase letters
toString() returns the value of a String object
toUpperCase() converts a string to uppercase letters
trim() removes whitespace from both ends of a string
valueOf() returns the primitive value of a String object